U.S. Department of Transportation Federal Aviation Administration Subject: AC34-1C FUEL VENTING AND Date: 05/09/2024 AC No: 34-1C EXHAUST EMISSION REQUIREMENTS FOR Initiated By: AEE-300 TURBINE ENGINE POWERED AIRPLANES Ralph Iovinelli This advisory circular (AC) contains information and provides guidance on the implementation of the fuel venting and exhaust emissions requirements for turbine engine powered airplanes that are required by Title 14 of the Code of Federal Regulations (14 CFR) part 34.
FAA Office of Environment and Energy AEE-300 Emissions Division
Advisory U.S. Department of Transportation Circular Federal Aviation Administration Subject: 14 CFR Part 34 - FUEL VENTING Date: 04/24/2024 AC No: 34-1C AND EXHAUST EMISSION REQUIREMENTS Initiated By: AEE-300 FOR TURBINE ENGINE POWERED
AIRPLANES
1. Purpose AC34-1C contains information and guidance concerning the regulations for fuel venting and exhaust emission requirements for turbine engine powered airplanes found in 14 CFR part 34 (hereinafter referred to as part 34). Part 34 is complex in that it reflects the following requirements:
• Sections 231-233 of the Clean Air Act (CAA) Title II, Part B: Aircraft Emission Standards, 42 USC 7571-7573;
• 40 CFR part 1031: Control of Air Pollution from Aircraft Engines;
• 14 CFR part 45: Identification and Registration Marking; and
• International Civil Aviation Organization (ICAO) International Standards and Recommended Practices, Annex 16, Volume II, Aircraft Engine Emissions Fourth Edition, July 2017, including Amendment 10 of January 1, 2021 (hereinafter referred to as A16V2) This AC provides guidance to individuals and agencies seeking to understand and implement the fuel venting, smoke, gaseous, and non-volatile particulate matter (nvPM) engine exhaust emission requirements for turbine engine powered airplanes as specified by part 34. This AC supersedes AC34- 1B, which has been cancelled. AC34- 1C provides material on new nvPM requirements adopted in part 34 to include the following:
• 2023 nvPM engine emission standards o Applicability of nvPM or smoke o Updated test procedures used to demonstrate compliance and determine maximum nvPM emissions throughout the thrust range;
• Required confidence interval calculations for nvPM emissions
• Updates to regulatory smoke number – applicability to engines greater than vs less than 26.7 kN and supersonic transport engines (Class TSS); and
• Updating references to the regulations of the Environmental Protection Agency (EPA) from 40 CFR Part 87 to 40 CFR Part 1031.
In addition, editorial changes have been made to the following:
• Differences between U.S. regulations and ICAO SARPs,
• Exemption process and associated Title 14 Sections,
• Description of the 2012 NOx regulations,
• Description of part 34 applicability to Unmanned Aircraft Systems (UASUASS), and
• Updates to information on test procedures incorporated by reference from A16V2.
Page 1 of 57
1. Purpose 1
1.1. Contents 2
1.2. Establishment and Implementation of Aircraft Emissions Regulations 5
1.3. Advisory Nature 6
1.4. FAA and EPA Regulatory Citations 6
1.5. Definitions and Abbreviations 6
1.6. Incorporation by Reference 6
1.7. Audience 6
1.8. Intent 6
1.9. Technical Advancement 7
1.10. Certification Process 7
2. Cancellation 8
3. References 9
4. Differences Between ICAO Annex 16 Volume II and 14 CFR Part 34 8
4.1. U.S. Regulation of Turboprops for Fuel Venting and Smoke Number 8
5. Sections 34.21, 34.23, 34.25 and 34.60 LTO Emissions and Maximum Emissions Throughout the Thrust Range 8
6. Part 34 Emissions Certification Test Plans and Test Reports 10
6.1 Part 34 Emissions Certification Test Plans 10
6.2 Part 34 Emissions Certification Test Reports 10
7. Part 34 Subpart A - General Provisions 11
7.1 Section 34.3 General Requirements 11
7.2 Section 34.5 Special Test Procedures 11
7.3 Section 34.7 Exemptions 12
7.4 Section 34.9 Exceptions 12
8. Part 34 Subpart B – Engine Fuel Venting Emissions (New and In-Use Aircraft Gas Turbine Engines) 13
8.1 Section 34.10 Applicability 13
8.2 Section 34.11 Regulations for Fuel Venting Emissions 13
1.1. Contents The information contained in this document sets forth acceptable means, but not the only means, by which compliance may be shown with the requirements of part 34.
TABLE of CONTENTS Page 2 of 57
9. Part 34 Subparts C and D - Exhaust Emissions (New and In-Use Aircraft Gas Turbine Engines) 15
9.1. Sections 34.10, 34.21, 34.23, 34.25, and 34.31 Applicability Dates 15
9.2. Section 34.21(e) Smoke exhaust emissions 15
9.3. Section 34.21 and 34.23 Hydrocarbon (HC) and Carbon Monoxide (CO) 16
9.4. Section 34.21 and 34.23 Oxides of Nitrogen (NOx) 17
9.5. Section 34.25 Non-Volatile Particulate Emissions Standards (nvPM) 17
9.6. Section 34.48 Emissions Test Requirements for Derivative Engines 18
10. Sections 34.10 and 34.21 Supersonic Aircraft Engine Emissions Regulations 19
11. Engine Emissions Regulations for Unmanned Aircraft Systems (UAS) / Advanced Air Mobility (AAM) 19
12. Commercial Space Vehicle Emissions 19
13. Part 34 Subpart G - Test Procedures for Engine Exhaust Gaseous Emissions (Aircraft and Aircraft Gas Turbine Engines) 20
13.1 Test Procedures Incorporated by Reference 20
13.2 Section 34.60 Introduction 20
13.2.1. Section 34.60(g) Calculation of Characteristic Emissions 20
14. 14.Part 34 Subpart H - Test Procedures and Compliance Demonstration for Non-Volatile Particulate Matter Emissions 21
14.1 14.1 Determining Maximum nvPMMC Values 21
14.2 14.2 Section 34.73 nvPM Demonstration of Compliance 24
14.3 14.3 Corrections to Reference Atmospheric Conditions 24
15. Guidance on ICAO A16V2, Appendix 7, Instrumentation and Measurement Techniques for nvPM Emissions 24
15.1. Appendix 7, 3.1: Data Required – nvPM emissions 24
15.2. Appendix 7, 4 General Arrangement of the nvPM Sampling and Measurement System 25
15.3. Appendix 7, 4.1 nvPM Sampling and Measurement System (connections) 25
15.4. Appendix 7, 4.4.1: nvPM Mass Measurement (instrument conformity) 27
15.5. 16.5 Appendix 7, 4.4.2 nvPM Number Measurement (instrument conformity) 27
15.6. Appendix 7, 5.1: Calibration and Maintenance 28
15.7. Appendix 7, 5.3: Carbon balance check for nvPM using air/fuel ratio (AFR) 30
15.8. 16.8 Appendix 7, 6.1.1: nvPM mass concentration correction for first stage dilution factor (DF1) 31
15.9. Appendix 7, 6.1.2: nvPM mass and nvPM number and CO2 only measurements for determination of EImass and EInum 31 Page 3 of 57
15.10. Appendix 7, 6.1.2: Examples of nv PM mass and nvPM number calculations using full gaseous emissions concentrations and simplified method 32
15.11. Appendix 7, 6.2.2: Correction for fuel composition using legacy, EEDB hydrogen to carbon ratio 34
15.12. Appendix 7, 7.2: Examples of splitter geometries and assemblies 34
15.13. Appendix 7, 7.2.6: Switching between CO, HC, and NOx measurements and nvPM measurement while in stable operating condition 36
15.14. Appendix 7, 7.2.6: Obtaining smoke measurements using the nvPM sampling system 36
15.15. Appendix 7, 7.5.1: Examples of system flow rates and system layouts for system flow control 36
15.16. Appendix 7, 8: Using thermal optical transmittance (TOT) analysis to determine elemental carbon mass as a surrogate for black carbon mass for calibration purposes 37
15.17. Appendix 7, 8: Clarification of terms in Appendix 7 38
15.18. Appendix 7, 8.2.1: Thermal optical transmission (TOT) method 38
15.19. Appendix 7, 8.3: Procedure to demonstrate conformity to performance specifications 40
15.20. Appendix 7, 8.3: Procedure to demonstrate conformity to nvPMmi performance specifications using a DFCAS 41
15.21. Appendix 7, 8.3.2: Measurement using a diffusion flame combustion aerosol source:
conformity demonstration and annual calibration 43
15.22. Appendix 7, 8.4.4: Determining the limit of detection (LOD) of the nvPMmi 46
15.23. Appendix 7, 8.5: Annual calibration using a DFCAS 47
15.24. Appendix 7, 8.5.6: Context of “as found” performance for nvPM mass instrument calibration 47
15.25. Appendix 7, 9.2.1: Context of “as found” performance for VPR calibration 47
15.26. Appendix 7, 9.2.2: Context of “as found” performance for CPC calibration 47
15.27. Appendix 7, 10: Additional system checks prior to an engine test 48
15.28. Appendix 7, 10.5.1.1: Ambient nvPM measurement 49
15.29. Appendix 7, 10.6: VPR dilution factor calibration check using real time measurements of CO2 49 16 Attachments to ICAO A16V2 50
16.1. Symbols 50
16.2. Attachment A, 1: Symbols 50
16.3. Attachment A, 1: Symbols 50
17. Basis of calculation of EI and AFR parameters 50
17.1. Attachment A, 2.1: Basis of Calculation of EI and AFR Parameters (AFR formulation) 50
17.2. Attachment A, 2.5: Basis of Calculation of EI and AFR Parameters (interference effects) 50 Page 4 of 57
18. Alternative Methodology — Numerical Solution 50
18.1 Alternative Methodology — Numerical Solution Additional Guidance 50
19. Additional Guidance 51
19.1 Engine Emissions Data Assurance Program (EDAP) 51
19.2 Additional Information 51
20. Attachment 1: 14 CFR 34.1 Definitions 52
21. Attachment 2: 14 CFR 34.2 Abbreviations 54
22. Attachment 3: ICAO Annex 16, Volume II, Amendment 9, July, 2017, Appendix 6, Table A6-1 56
1.2. Establishment and Implementation of Aircraft Emissions Regulations The United States is one of 193 signatory States to ICAO’s Convention on International Civil Aviation, also known as the Chicago Convention. Under Article 12 of the Chicago Convention, each contracting State agrees to keep its own regulations uniform, to the greatest extent possible, with those established under the Chicago Convention. Domestically, under 49 U.S.C. § 40105(b)(A), the Secretary of Transportation and Administrator of the FAA are required to act consistently with obligations of the United States Government under an international agreement such as the Chicago Convention, As part of ICAO’s standard setting process regarding aviation emissions, the FAA leads the U.S.
delegation with assistance from EPA. FAA, EPA, industry representatives, and foreign certification authorities all participated in a multi-year process that resulted in the nvPM standards adopted by the ICAO, which the EPA thereafter adopted in 40 CFR part 1031.
This rulemaking adopts the procedures necessary for the FAA to implement the regulatory standards and test requirements for nvPM emitted by aircraft engines adopted by the EPA under 42 U.S.C. § 7571 (§ 231 of the Act) (87 FR 72312, November 23, 2022) that were effective December 31, 2022.
Section 7571 of the CAA states the following:
(2)(A) The [EPA] Administrator shall, from time to time, issue proposed emission standards applicable to the emission of any air pollutant from any class or classes of aircraft engines which in his judgment causes, or contributes to, air pollution which may reasonably be anticipated to endanger public health or welfare.
(B)(i) The [EPA] Administrator shall consult with the Administrator of the Federal Aviation Administration on aircraft engine emission standards.
(ii) The [EPA] Administrator shall not change the aircraft engine emission standards if such change would significantly increase noise and adversely affect safety.
The FAA is statutorily required (see 42 U.S.C. § 7572 (§ 232 of the Act)) to incorporate the EPA’s nvPM emissions standard into its regulations (14 CFR part 34) and apply the EPA-designated test procedures that allow applicants to demonstrate compliance with the emissions standards at the time of engine airworthiness certification. The FAA has no authority to alter the standards or test requirements adopted by the EPA for engine emissions.
As a signatory to the Chicago Convention, the US must establish standards that have the highest practicable degree of uniformity to the ICAO Standards and Recommended Practices (SARPs) or file a difference. US federal agencies also consider impacts of regulatory actions under a variety of executive orders and other requirements.
Page 5 of 57
To meet its obligations under the Chicago Convention, the U.S. Government considers the standards and recommended practices adopted by ICAO. The EPA, using its authority under the CAA, then adopts the same or similar aircraft engine emissions standards through the U.S. rulemaking process, with public notice and opportunity to comment, prior to their being adopted in 40 CFR part 1031, once final. The FAA then implements the EPA standards by enforcing them at the time of aircraft engine certification under part 34. Consequently, regulated entities and certification staff should be aware that there will be a time lag in the adoption of ICAO’s new regulations in the U.S. as the two agencies take their required actions under the CAA. In the event there is a change to 40 CFR part 1031 that has yet to be adopted into part 34 at the time of engine certification, 40 CFR part 1031 is the applicable U.S. regulation.
1.3. Advisory Nature The language in this document is intended to be permissive and advisory in nature, except when regulatory text is specifically cited. In addition, compliance methods are generally chosen by an applicant within the framework of the regulation as written. Terms such as “must” and “shall” are only used in this AC when directly referring to requirements defined in regulatory text (e.g., 14 CFR part 34) . Nothing in the is AC may be interpreted as changing any regulation or its requirements, and does not authorize changes in, or deviations from, any regulatory requirement.
1.4. FAA and EPA Regulatory Citations This AC uses citations from the FAA regulations in 14 CFR part 34, and a citation for the corresponding EPA regulation in 40 CFR part 1031, with the latter appearing in parenthesis and italics . For example, reference to the fuel venting requirements of 14 CFR 34.11 will appear with reference to the equivalent EPA regulations in 40 CFR part 1031 as “14 CFR 34.11 (40 CFR 1031.30(b)).”
1.5. Definitions and Abbreviations Attachment 1 of this AC includes the definitions found in 14 CFR 341. Attachment 2 of this AC includes all abbreviations found in 14 CFR 34.2 and throughout this AC.
1.6. Incorporation by Reference The engine emissions measurement and test procedures of ICAO A16V2, Appendices 1-7 have been incorporated by reference in subpart G of part 34. Incorporated material is considered part of U.S.
regulatory requirements. Note: EPA has also incorporated, by reference, the measurement and test procedures of ICAO A16V2 into its regulations in 40 CFR 1031.210. The EPA has also incorporated Appendix 8 to Volume 2, which covers procedures for estimating nvPM system loss corrections. System loss correction data is required in EPA’s annual production reports as specified in 40 CFR 1031.150(c)(6)(ii), (iii) and (v). Those reporting requirements are specific to EPA regulations; FAA’s reporting requirements only pertain to the submission of emissions test reports, discussed in 6.2 of this AC.
1.7. Audience The intended audience for this AC includes engine specialists and propulsion engineers from the FAA’s Aircraft Certification Service (AIR) and aircraft certification branches, aircraft and aircraft engine industry specialists, aircraft certification applicants, Designated Engineering Representatives (DERs), Organization Designation Authorization (ODA) Unit Members (UMs), other certification authorities, airline customers, airport operators, the engineering and scientific communities, and other persons that are interested in the certification of aircraft engines for fuel venting, smoke, gaseous emissions, and nvPM.
1.8. Intent The intent of this AC is to present the FAA’s explanation of selected portions of the aircraft engine emissions regulations and certification requirements contained in part 34. This AC also presents some historical policies, examples, interpretations and further guidance that have been used in the aircraft engine certification process.
Page 6 of 57
1.9. Technical Advancement Since the introduction of aircraft engine emission regulations in the United States in 1973 1, acceptable means and procedures for emissions measurement, testing, data management, evaluation, and compliance reporting have advanced considerably. In seeking compliance with the certification requirements, applicants may submit (and may receive approval to use) engine-specific alternative and equivalent testing, measurement, and data reduction procedures that reflect these advances. Approval of such alternatives2 is granted by the FAA’s Office of Environment and Energy (AEE), at FAA Headquarters in Washington DC. For further information, see 6.1 of this AC.
1.10. FAA Certification Process As a part of its certification responsibilities, the FAA reserves the right to observe aircraft engine emission tests3, or the agency may delegate that responsibility to the engine manufacturer through a designee4 or Organizational Designation Authorization5 (ODA). Every applicant for an engine type certificate must comply with the emissions requirements of part 34 6.
More detailed information on the FAA’s certification process and procedures may be found in FAA Order 8110.4C7, Type Certification, and the FAA and Industry Guide to Product Certification, Third edition, May 2017.8 The FAA’s Office of Environment and Energy (AEE) is responsible for answering any questions or approving any deviation from the requirements of part 34. Once an engine type certificate is issued, an OEM may elect to provide engine emissions certification data to AEE for review followed by submission of the data to ICAO’s Aircraft Engine Emission Data Bank (EDB)9.
2. Cancellation Advisory Circular 34-1B Fuel Venting and Exhaust Emission Requirements for Turbine Engine Powered Airplanes, dated June 27, 2003, is canceled.
1 38 FR 19088, July 17, 1973 2 Including variations from test fuel specifications in A16V2, Appendix 4 3 14 CFR § 34.3(p) 4See 14 CFR part 183, Representatives of the Administrator 5 FAA Order 8100.15B, Organizational Designation Authorization Procedures 6 14 CFR § 33.1(b) 7 https://www.faa.gov/regulations_policies/orders_notices/index.cfm/go/document.information /documentid/15172 8 https://www.faa.gov/aircraft/air_cert/design_approvals/media/CPI_guide.pdf 9 https://www.easa.europa.eu/easa-and-you/environment/icao-aircraft-engine-emissions-databank Page 7 of 57
3. References
(1) 42 USC Part B, §§ 7571-7573 Aircraft Emissions Standards
(2) 14 CFR part 1, §1.1 General Definitions
(3) 14 CFR part 21, §21.93 Classification of Changes in Type Design
(4) 14 CFR part 25, § 25.903 Engines and § ad its Appendices as follows: 25.951 General
(5) 14 CFR part 34, Fuel Venting and Exhaust Emission Requirements For Turbine Engine Powered Airplanes
(6) 14 CFR part 45, Identification and Registration Marking
(7) 40 CFR part 1031, Control of Air Pollution from Aircraft Engines (formerly 40 CFR part 87 prior to adoption of the nvPM regulations)
(8) 40 CFR part 87, Control of Air Pollution from Aircraft and Aircraft Engines (now reorganized under 40 CFR part 1031)
(9) FAA Order 8110.4C, Type Certification
(10) FAA Order 8100.15B, Organizational Designation Authorization (ODA) Procedures
(11) FAA and Industry Guide to Product Certification, Third edition, May 2017
(12) ICAO Aircraft and Emissions Databank (https://www.easa.europa.eu/easa-andyou/environment/icao-aircraft-engine-emissions-databank)
(13) ICAO, International Standards and Recommended Practices, Annex 16, Environmental Protection, Volume II, Aircraft Engine Emissions Fourth Edition, July 2017, and its revisions and appendices as follows: Volume 2 Amendment 10 of January 1, 2021, incorporated by reference in 14 CFR part 34 (40 CFR part 1031); Appendices 1, 2, 4 and 6 as applicable to smoke emissions; Appendices 1, 3, 4, and 6 as applicable to gaseous emissions, and Appendices 1, 4, 6, and 7 as applicable to nvPM emissions. Appendix 5 applies to gaseous emissions and smoke for afterburning engines.
(14) ICAO Annex 16 Volume II Environmental Technical Manual – Procedures for Emissions Certification of Aircraft Engines Second Edition, October 2017
(15) SAE--International Aerospace Recommended Practice (ARP() 1179D, Aircraft Gas Turbine Engine Exhaust Smoke Measurement, July 2011
(16) SAE-International ARP1256D , Procedure for the Continuous Sampling and Measurement of Gaseous Emissions from Aircraft Turbine Engines, July 2011
(17) SAE-International ARP1533B, Procedure for the Analysis and Evaluation of Gaseous Emissions from Aircraft Engines, January 2013
(18) SAE-International ARP6320, Procedure for the Continuous Sampling and Measurement of Non-Volatile Particulate Matter Emissions from Aircraft Turbine Engines
(19) SAE-International ARP6481, Procedure for the Calculation of Sampling Line Penetration Functions and Line Loss Correction Factors
4. Differences Between ICAO Annex 16 Volume II and 14 CFR Part 34
4.1. U.S. Regulation of Turboprops for Fuel Venting and Smoke Number The U.S. fuel venting regulations of 14 CFR 34.11 (40 CFR 1031.30 (b)(iii)) apply to all turboprop engines regardless of rated output (rO). That regulation prohibits the venting of liquid fuel after engine shutdown.
The smoke number limits in 34.21(e)(3) (40 CFR 1031.40(a)) apply to turboprop engines with a rO equal to or greater than 1,000 kilowatts (kW). The regulations specify a maximum SN limit of 187(rO)-0.168 across the full engine thrust range.
Annex 16 Volume 11 has no equivalent standards for fuel venting or smoke that apply to turboprop class engines. That Annex only applies to turbofan and turbojet class engines.
Page 8 of 57
Mode Class
TP TF, T3, T8 TSS TIM (min) % of rO TIM (min) % of rO TIM (min) % of rO Taxi/idle 26.0 7 26.0 7 26.0 5.8 Takeoff 0.5 100 0.7 100 1.2 100 Climb out 2.5 90 2.2 85 2.0 65 Descent NA NA NA NA 1.2 15 Approach 4.5 30 4.0 30 2.3 34
5. Sections 34.21, 34.23, 34.25 and 34.60 LTO Emissions and Maximum Emissions Throughout the Thrust Range Pollutant limits found in part 34 (40 CFR 1031) apply to the “characteristic” test values for each pollutant.
The characteristic value is calculated by following the requirements of A16V2, Appendix 6, where a factor, which depends on the number of engines tested, is applied to the emissions test results for each pollutant. If complete emissions test data is submitted from more than one engine, the characteristic value of a pollutant decreases with the application of the Appendix 6 factor corresponding to the higher number of test engines from which test data is obtained.
Regulatory limits in part 34 apply to the characteristic pollutant levels based on an LTO weighted test cycle for all gaseous emissions, nvPMmass and nvPMnum. For SN and nvPMMC, the regulatory limit is based on the characteristic maximum value throughout the full thrust range. See Section 14 of this AC for further information on nvPMMC. Applicability for each pollutant is summarized below:
LTO weighted test cycles for the various classes of engines are defined in 14 CFR 34.60 (f) (40 CFR 1031 .140(e)) and are based on time in mode (TIM) and thrust settings (% rO) as follows:
LTO Test Cycles and Times in Mode
6. Part 34 Emissions Certification Test Plans and Test Reports
6.1. Part 34 Emissions Certification Test Plans Prior to undertaking an emissions certification test, the applicant is expected to submit an emissions compliance test plan to the FAA that describes the method(s) by which the applicant proposes to show compliance with the emissions requirements. Approval of test plans and test reports may not be delegated to a designated engineering representative (DER) or Organization Delegation Authorization Page 9 of 57
(ODA) holder; test plans and reports must be approved by FAA certification staff. Approval of any equivalent test procedure must be done in accordance with § 34.60(e) and § 34.71(e)(2) which are discussed in 7.1 and 7.2 of this AC.
Emissions compliance test plans should include the following types of information:
a) Introduction: a description of the engine emissions certification basis, i.e., the applicable amendment of part 34.
b) Engine description: type, model number and specific details of the basic engine configuration to be certified;
c) Engine emissions certification methodology: test concepts, equivalent procedures, and technical procedures. Equivalent procedures may not be delegated and must be approved by FAA staff (see
7.2 of this AC on Special Test Procedures):
d) Test description: test methods that comply with the emissions regulations;
e) Measurement system: a description of measurement and sampling system components and procedures, including calibration procedures, that are intended to be used to demonstrate compliance with the emissions regulations; and
f) Data evaluation procedures: data evaluation and correction procedures to be used in compliance with the provisions of part 34:
6.2. Part 34 Emissions Certification Test Reports Emissions Certification Test Reports should reflect compliance to engine emissions regulatory limits and other requirements in part 34. In accordance with 14 CFR § 21.20(b), type certification applicants must provide a statement certifying that the applicant has complied with the applicable requirements.
For engine type certification, applicants should include the required compliance statements in its emissions certification test reports and include the characteristic values for all gaseous and nvPM emissions.
Other information in emissions certification test reports that support the compliance statement of § 21.20
(b) may include the following:
Test Procedures
• Acknowledgement that the test procedures were conducted according to the emissions certification test plans and, the applicable requirements of part 34;
• Description of, or reference to, the applicable procedures that were followed, e.g.:
• Emissions sampling probe, or rake, validation
• Emissions test set-up and procedures
• Test fuel specifications
• Instrumentation
• Calibration
• Quality assurance and procedural checklists Data
• Emissions test data results
• Method of data acquisition
• Required calculations
• Required corrections
• Any other data requested by FAA Page 10 of 57
Section 34.73(e) identifies the information to be included in an emissions test report, once nvPM emissions certification testing is complete.
Note:EPA has additional reporting requirements as specified in 40 CFR 1031.150, including nvPM loss corrections. This AC does not address those requirements, because the FAA does not collect or use that information.
7. Part 34 Subpart A - General Provisions
7.1. Section 34.3 General Requirements Section 34.3(a):
In the United States the legal authority to establish and enforce aircraft engine emissions standards is done by two agencies. The CAA authorizes the EPA to establish aviation emission regulations (42 USC 7571) which it publishes in 40 CFR part 1031. Section 7572 of the CAA requires the FAA to enforce the standards adopted by the EPA at the time of aircraft certification, which the FAA publishes in 14 CFR part
3. EPA and FAA are required to consult with each other in the establishment and enforcement of aircraft engine emissions regulations. Within the FAA, the rulemaking to revise part 34, to set policy and to coordinate with the EPA are accomplished by the Office of Environment and Energy (AEE). AEE is assisted in the implementation of these actions by the Aircraft Certification Service (AIR). See 1.2 of this AC, Establishment and Implementation of Aircraft Emissions Regulations, for more discussion of the relationship between the FAA and EPA and the adoption of regulations to conform to ICAO SARPs.
Section 34.3(i) and (j):
Both 14 CFR part 34 and 40 CFR part 1031 provide for alternative (or “special”) test procedures; such procedures must be approved in advance of engine emissions testing. See 7.2 of this AC on § 34.5, Special Test Procedures, for further guidance.
Section 34.3(k):
Wherever 40 CFR part 1031 requires agreement, acceptance, or approval by the Administrator of the EPA, part 34 requires a showing that such agreement or approval has been obtained.
Manufacturers that seek agreement, acceptance, or approval by the Administrator of the EPA are requested to coordinate with AEE, in advance of certification testing, which will coordinate with EPA’s Designated Program Officer. Agreements, acceptance, or approval must be signed off by both EPA’s Designated Program Officer and AEE and should be added to emissions certification test plans and reports. Agreements, acceptance, or approvals apply to specific, individual emissions test programs and are not to be considered applicable to other test programs.
7.2. Section 34.5 Special Test Procedures A manufacturer or operator of aircraft or aircraft engines may submit a written request to use special (or alternative) test procedures. Any procedures that deviate from the test procedures specified in A16V2 Appendices 1 through 7 for the measurement and calculation of smoke number, gaseous or nvPM emissions (i.e. “special test procedures”) must be approved by the FAA prior to the engine test.
Manufacturers and operators may request approval of special test procedures by submitting their written request, with supporting justification, to the FAA Office of Environment and Energy. The FAA will coordinate with EPA’s Designated Program Officer for approval, as required by statute or regulation.
Sections 34.60(e) and 34.71(e)(2) specify that, for special test procedures to be approved, one of the following conditions must be met:
(1) The engine cannot be tested using the procedures specified in a regulation; or Page 11 of 57